From the Director

Rex

 

 

 

by Rex Parker, Director

Reflecting over the past year in AAAP. As we head toward solstice and the conclusion of 2016 a look into the mirror seems appropriate. It’s been an honor for me to continue to serve as director. We’ve had wonderful speakers’ presentations thanks to the program committee, and we’re grateful to Princeton Univ. and the Astrophysics Dept. for use of the terrific venue that is Peyton Hall. Our tradition of public outreach continued at WC Observatory and on the road, thanks to efforts of keyholders and observatory co-chairs. Here are a few of the highlights.

  • Outstanding programs in 2016 included talks by Dr Jim Green, Director of NASA’s Planetary Sciences division; Dr Jim Stone, new chairman of Princeton Astrophysical Sciences; the documentary movie “Saving Hubble” presented by its director David Gaynes; and a discussion by author Frank O’brien on “The Apollo Guidance Computer” (his book is available on Amazon).
  • A newer Celestron 14” telescope was installed at WC Observatory, with noticeably better off-axis optical performance than the previous model. The new C14 was the last component of a generous donation received a few years ago (along with Paramount #2 and the aluminum Observa-Dome which we gave to another organization a year ago).
  • Other changes at the Observatory included modernizing the computers and preparing for the jump to The SkyX software to control the two Paramount-ME’s, and a new video monitor for the Mallincam-5”refractor. These efforts were led by Observatory Chair Dave Skitt and others. Verizon FiOS was installed giving us high speed internet and telecomm at the Observatory, thanks to member Jim McHenry.
  • Night-sky refresher sessions were held at the NJ State Museum Planetarium, including “Planetarium Retro”, helping members better understand and more effectively show others the deep sky as seen in central NJ. Thanks to Bill Murray for hosting these events.
  • Our new improved website came alive with content showing AAAP to the on-line world. Thanks go to webmaster Surabhi Agarwal for redesigning and configuring the site.
  • We now claim 3 Mercury transit observations over 3 centuries with the Hastings 6” refractor telescope at WC Park (1881, 1973, 2016), a feat unmatched anywhere in the world to the best of our knowledge. The authenticity of this claim is based on historical research by John Church (see May 2016 issue of Sidereal Times). Thanks to John Church, Bill Murray, Gene Ramsey, Larry Kane, and Dave & Jenn Skitt for organizing the May event. The Dec 2016 issue of Sky and Telescope features an article “Three Centuries, One Scope” about this historic achievement along with a photograph of members alongside the Hastings refractor at the Observatory – see this link http://www.nxtbook.com/nxtbooks/newtrack/st_201612/index.php#/86
  • More history – 150 years of the Rutgers Schanck Observatory. Ten AAAP members attended a celebration hosted by the Rutgers Cap & Skull Society, unveiling the renovated Schanck Observatory on the Queens campus. The presentation included the restoration of the building and telescope, and it was noted that AAAP’s 6” Hastings refractor spent 3 decades as the telescope mounted in the Schanck (ca. 1904-1937).
  • To acquire another telescope to co-mount with the Hasting 6” refractor on the 2nd Paramount, the Board authorized expenditure of up to $10,000. After researching the topic, we acquired a pristine Takahashi Mewlon 250, a 10” f/12 Dall-Kirkham Cassegrain telescope. This high quality instrument has a 3-meter focal length and offers high resolution and contrast, and now sits alongside the Hastings refractor.
  • Jersey StarQuest was successfully held in Hope NJ at the end of October. With 16 telescopes and 22 people on the observing field for one beautiful clear and cold night, we kept alive the ~25 year tradition in the club of an annual dedicated observing weekend at a relatively dark sky site.
  • Fate of AAAP’s UACNJ Jenny Jump Observatory came to the forefront. The Board on Aug 23 resolved to continue AAAP’s commitment to the United Astronomy Clubs of New Jersey Observatories at Jenny Jump State Forest. A proposal to repair the observatory and upgrade equipment is being developed, and will continue to be a topic needing further attention by members in 2017.
  • RIP Gene Ramsey, who passed away Sept 9. AAAP members share a deep sense of loss for our esteemed astronomer and friend. Gene was AAAP’s long-time Observatory co-chair, one of our most expert observers, and a wizard at dreaming up new gizmos and accessories to use with telescopes and mounts.

Remember the night of the Supermoon, Nov 13 2016. The November full moon often occurs when the elliptical orbit brings the moon closest to earth, and this year it was closest in our lifetimes for many of us (since 1948). Here’s my attempt at photographing it that night, along with a poem (first published in ST Dec 2014, edited 2016) to close the year in Sidereal Times.

rex-dec-2016-b

Sharp are these cold nights

Moon and frost earth’s shadow share

Stars beckoning beyond globe’s rim

Waypoints and patterns for closing eyes.

We dream in these wintry climes

Wishing heaven to be our home

Wrapped in misting clouds embrace

Chilled yet warmed by lunar light.

                                               – R A Parker –

 

Posted in December 2016, Sidereal Times | Tagged , | 1 Comment

The Other 95%: Revealing the Dark Universe – Dec. 13, 2016 Lecture

by Ira Polans, Program Chair

The December AAAP club meeting will be held on December 13 at 7:30PM in Peyton Hall on the Princeton University campus. The night’s talk is titled “The Other 95%: Revealing the Dark Universe” by Dr. Eric Gawiser, Associate Professor in the Department of Physics & Astronomy at Rutgers University.

Dr. Eric Gawiser

Dr. Eric Gawiser

Dr. Gawiser’s talk is about the mysterious universe we live in. Only 5% of its energy takes the form of regular matter (i.e., protons, neutrons, and electrons). Astronomers focus most of our research on this 5%, because it gives off light that we can study directly. Nonetheless, we have been able to infer that 25% of the universe’s energy is in the form of a different kind of matter that does not give off light, called dark matter, and that the remaining 70% is composed of an even more mysterious energy possessed by empty space, called dark energy. The dark matter has sufficient gravity to hold galaxies together such that their stars do not fly apart. The dark energy is causing the expansion of the universe to accelerate, as discovered in 1998 in what remains the most surprising scientific development of the past two decades. Dr. Gawiser will offer a gentle introduction to the Dark Universe and will describe the next generation astronomical surveys seeking to reveal the true nature of dark matter and dark energy.

Prior to the meeting there will be a meet-the-speaker dinner at 6PM at Winberie’s in Palmer Square. If you’re interested in attending please contact program@princetonastronomy.org no later than noon on December 13.

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Minutes of the November 8, 2016 Meeting of the AAAP

by James Poinsett, Secretary

• Rex called the meeting to order and outlined the agenda for the evening. He also read a letter to the club from Gene Ramsey’s widow.
• After the lecture StarQuest 2016 was discussed. There were 22 people, 16 telescopes and good, mostly clear conditions Friday night. Clouds rolled in on Saturday and the night was cancelled. StarQuest 2017 will be weekend of 9/17 or 9/24.
• There was a visit to Jenny Jump during StarQuest. A work party is needed to fix the casters on the roll off roof. Email Dave at observatory@princetonastronomy.com if you are interested in joining the work party.
• A couple of eyepieces dedicated for the Mewlon telescope are needed. It would be about $800 and is part of the original expenditure approved for the scope. An aperture mask is needed for lunar observing while using the Mewlon.
• The treasury is in good shape, approximately $20K.
• No outreach events at this time.
• Bill Murray attended the Stokes Star Party. He said the site is very good, possibly better than Hope Conference Center. The party is twice a year and is highly recommended.
• The Nov 19th event with the Friends of Washington Crossing Park has been postponed, no new date has been set.
• The meeting was adjourned a bit early because it was election night.

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Moon Over Mexico

Photo Credit: Joe Bezzina

Photo Credit: Joe Bezzina

 

Posted in December 2016, Sidereal Times | Tagged | Leave a comment

Snippets

compiled by Arlene & David Kaplan

James Webb Telescope. Credit: NYT

James Webb Space Telescope. Credit:NYT

Telescope That ‘Ate Astronomy’ Is on Track to Surpass Hubble
Like the petals of a 20-foot sunflower seeking the light, the 18 hexagonal mirrors that make up the heart of NASA’s James Webb Space Telescope were faced toward a glassed-in balcony overlooking a cavernous clean room at the Goddard Space Flight Center here….more

Pluto. Credit: NASA/JHUAPL/SWRI

Pluto. Credit: NASA

Pluto ‘has slushy ocean’ below surface
Pluto may harbor a slushy water ocean beneath its most prominent surface feature, known as the “heart”. This could explain why part of the heart-shaped region – called Sputnik Planitia – is locked in alignment with Pluto’s largest moon Charon…more

Roundest object in space. Credit: BBC

Roundest object in space. Credit: BBC

‘Roundest known space object’ identified
Astronomers claim to have discovered the roundest object ever measured in nature. Kepler 11145123 is a distant, slowly rotating star that’s more than twice the size of the Sun…more

Ariane Launch. Photo: ESA

Ariane Launch. Photo: ESA

Europe launches Galileo satellite quartet
Europe has extended its satellite-navigation system by putting another four spacecraft in orbit. They went up on an Ariane 5 rocket from French Guiana, leaving the ground at 10:06 (13:06 GMT)…more

Credit: NASA

Credit: NASA

NASA and FEMA Rehearse for the Unthinkable
Imagine if scientists discovered that an asteroid was hurtling toward Los Angeles. The possibility has existed on the pages of Hollywood scripts. But in what may be a case of life imitating art, NASA, the Federal Emergency Management Agency and other government agencies engaged last month in a planetary protection exercise to consider the potentially devastating consequences of a 330-foot asteroid hitting the Earth…more

Credit: NYT

Credit: NYT

Earth, the Final Frontier
Rochester — On April 1, 1960, the newly established National Aeronautics and Space Administration heaved a 270-pound box of electronics into Earth orbit.
Tiros-1 was the first world’s first weather satellite. After its launch, Americans would never again be caught without warning as storms approached…more

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Cosmic Fireworks

by Prasad Ganti

Stars are born, they live, and then they die. Like any living beings. They are born when lot of gas and dust comes together under the influence of gravity and a nuclear furnace gets lit. Hydrogen powers a star. The star glow converts hydrogen to helium in a nuclear reaction termed as fusion. When the hydrogen supply is exhausted, the star starts to die. The type of death depends on the size of the star.

Stars come in different sizes. Small and medium stars live longer and die a calmer death and end up as white dwarfs. While the heavier stars live for shorter time and die a violent death. Of course, there are some fireworks when a star dies. Smaller stars have smaller fireworks while the bigger ones have fireworks comparable to Disney World fireworks or the Fourth of July fireworks !

Towards the end of their lives, the stars give off the matter as gas and dust into surrounding space. This remnants form the raw material for the birth of the next star. Or even a next generation star. The process of giving out matter also results in radiation, like light, gamma rays etc. This results in an explosive end. Heavier stars light up as a supernova before finally becoming a neutron star or a black hole. Both the neutron star and a black hole are gravitationally intense astronomical objects.

Supernova forms the death throes of a heavy star. Our Sun being a middle sized star will not result in one. Several solar masses are required to form a supernova. Supernovae are not very common. Occurring about two a century in our Milky Way galaxy. Fortunately, none of them in our solar neighborhood. If it occurs so close by, we would not exist to notice it. They occur at a safe distance away from us.

The supernovae occurring in our galaxy are visible to the naked sky. But the ones in other galaxies need a telescope to watch. The brightest portion lasts for a short period of time. About days and months. Chinese astronomers observed a supernova in 1054 AD. This supernova has cooled off since then and is visible now as Crab Nebula in the constellation of Taurus.

A supernova was observed in 1987 and is named as 1987a, which was visible in the region of Large Magellanic Cloud. This cloud can be seen only from the southern hemisphere. A 13 second burst of neutrinos was observed and detected by several observatories all over the world. This was the grandest supernova observed since the invention of the telescope. Which one is next ?

Betelgeuse is a dying red supergiant star. It lies in one of the corners of the constellation Orion, the Hunter. It is visible to the naked eye with a tinge of redness. At about 640 light years away, given its massive size, it is not that far. But not close either because this star will end up its life as a supernova. When it happens, it will be the brightest object in the night sky, next to the Sun and the Moon. It will produce great Cosmic fireworks. When will it happen ?

Despite all the advances in astronomy, it is very difficult to predict when a star will become a supernova. It is very much like predicting the death of an individual human being. A patient may be on his or her last legs in the Intensive Care Unit. But when would the end come is anyone’s guess. Betelgeuse may explode in our life time, or in the next hundred years or even a thousand years or a hundred thousand years. Not likely to be millions of years.

One more reminder that astronomical distances are so huge that even light takes some time to travel across. Betelgeuse is 640 light years away. Which means that when we look at this star, we are looking at it as it existed 640 years ago. How does it look today ? We will have to wait 640 years to know the answer ! It will take 640 years before we know that Betelgeuse has exploded.

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Near Infrared Telescope or how I said no to Cal-Tech

by Ted Frimet

Ok, so maybe it isn’t so fair of me to say, I said “no” to Cal-Tech. What really happened was that I stumbled upon their article, on infrared astronomy. And right out of the gate they designated infrared astronomy, as no-go territory for any amateur. And that got my attention, and I hope I got yours.

As my article on how to build a near infrared telescope is really very brief, I’d like to take more time, and invest you in my history of how I arrived at this point. Thank you. I must apologize, up front; I compose most of my writing, and dialogue in stream of consciousness. This may appear to be word salad to some, or a very appetizing main course for a few. You decide. What is really very cool, is that AAAP has provided a place, where some, or all of this text becomes web searchable, and may become the jumping off point for some young minds. So, with that in mind, I thank you, once again.

It was over three years ago when I stumbled upon micro-controllers, specifically the Arduino and its derivatives. I was wowed and amazed that during my lifetime, I could interact with a technology that was not only understandable, but also very affordable. Step by step, I learned how to program an Arduino and to control real world devices. Ok, not so, “real world”, however LED’s, LCD’s as output devices, and temperature and barometric pressures sensors, as input devices, count as “real”, don’t they ?

By the end of November 2015, I had cobbled together a poor mans LIDAR prototype. It was the result of a failure, actually. The story goes, that one day, as I was pondering the output of a BMP180 (barometric/pressure /temperature /altitude etc. sensor) I looked up. Yup, at the sky. And thought that the pressure reading I was observing was the direct consequence of pressure – right over my house. I then, thought, rather naively, that there were pressure waves that were forming clouds, directly overhead. And I started to think of where those pressure waves were coming from. And of course, silly me started to think of photonics pressure, from outside of our atmosphere shaping the clouds. A year later, I would be viewing sun spots (as I learned – at the lowest level of possible observation during the current cycle) and thinking of cloud formations as a result of those same solar observations. You could shoot holes through the aforementioned hypothesis. But you got to agree, at least it got me thinking. But I digress.

The failure wasn’t in trying to measure barometric’s. I was going to image the underside of cloud formations using a small grid of light sensitive resistors. The array soldering process was troublesome and painstakingly difficult, and before I could finish the array – A friend of mind quietly pointed out that the sensors I was employing could not possibly work in the fashion that I had designed. Too wide a viewing angle for any one sensor, it appears, is a failure for this application. However, during the project, I had decided to measure cloud height. That was a success. It was a success borne out of failure. I couldn’t be more pleased.

I built a prototype that measures cloud height. You can search YouTube for mrtfrimet, or Arduino Cloud Height Sensor, and find the three videos that discuss this in detail. Here is a brief: I utilized a Melexis infrared sensor, two barometric and temperature sensors (to average out any errors), and some insight from a children’s web page sponsored by NASA to better understand dew point. Also, I stood on the shoulders of giants that had previously programmed the libraries of my chosen devices – which cut down on development time, immensely. The result was spot on. And I have published the data on the web. It is public domain on Frizting. The breadboard PDF looks dandy, but the wiring is a mess. Not for the weak of heart, I suppose.

Back to the failure…When I came to terms that I could not image the underside of cloud cover, with my current build, I though of repurposing my prototype. And turned to infrared astronomy. It seemed particularly important to me, at the time, to think that since I worked with an IR sensor, that I could do IR astronomy. Clearly I had a lot to learn.
I figured on 12 to 18 months of learning how to make back yard observations, as a precursor to any prototype building. And here I am, today, with you, AAAP, learning during our public night viewings, StarQuest, and UACNJ dark sky at Jenny Jump. I learn more and more with every view, and am incredibly honored that those with decades of experience share their wisdom, and intellect with me, without so much as a second thought.

So, here I am, on the forefront of having acquired some amateur astronomer knowledge, that by February 2017, I should have enough experience to see the night sky, and appreciate the results in near infrared.

The poor man’s lidar, although a success in cloud height measurement, will not work in measuring near infrared – not in the way I thought of, a year ago. Not without modification, and possible destruction. And the sensors that can do the job, require cooling to 77K. Working with liquid nitrogen and dewer containers are not immediately within the grasp of my abilities. I can dream of doing that, some day. However, today is not that day. So I take a pass, for now, on low temperature sensors requiring the aforementioned -321 degree Farenheit cooling apparatus.

After searching the web for eyepiece and sensor information on CaF2, NaCL, ZnFe, KRS-5, AgCl, KBr, diamond, and lnSb, I stumbled across the more pedestrian and commonplace (to me anyway) germanium. It seems that Texas Instruments makes the OPT 101 in a plastic dual inline the is sensitive to 700nm thru 1100nm. And it does its job at room temperature.

Now before you get up and leave, let me shout out, something, here, on the nature of the bandwidth that I will be studying. It is a pretty clear fact that our atmosphere interferes with the electromagnetic spectrum, and infrared isn’t any exception. However, I’d like you to know how excited I am to find a sensor that can detect near infrared, and not require cooling. The OPT 101 was used in a medical prototype, for measuring some metrics concerning blood flow. So clearly, no liquid Nitrogen, and safe enough to be around sentient life forms. And it does have a response rate to a narrow band that corresponds to near infrared.

The other problem. My first scope, a 4.5 inch Newtonian acquired thru goodwill, has silvered mirrors. Not necessarily the best choice to reflect near infrared. A visitor and participant at our AAAP Star Quest, who is employed by a manufacturer of eye pieces, enlightened me that our reflectors can be bandwidth tuned. He even opted for dielectric coatings on his own telescope. Needless to say, he got my full attention. My mirrors could be recoated and made specific to reflect the narrow bandwidth that I’ve chosen to study. I think that this is called bandwidth tuning. But I like the poor mans approach. Ebay 24K gold leaf for a couple of dollars, and apply it to the primary and secondary mirrors. Gold reflects infrared, nicely. Wouldn’t you agree? However, the mechanics of removing a mirror, applying gold leaf, reinstallation, collimation, OH MY!! I am out of my league, not ever having removed a mirror or collimated in my life. I trust that you all have my back, to lend a hand, to collimate what will, no doubt, be the undoing of my first telescope. I will do a trust fall, right here and now. Be ready to breathe life back into my telescope!

Collimation. I suppose that collimating is easiest when you can see full spectrum light, but now I’ve coated my mirrors with gold. That makes it downright difficult. So I made it a thought experiment, and my hypothesis is that gold will reflect yellow and red light. And we should be able to “see” the “eye” to make adjustments. Fine tuning will have to wait to position a star, in mid field, and gauge the output of the prototype. No doubt of that.
And the next problem, yet. Infrared energy doesn’t play nice with optics. I started to research, CaF2, NaCl, ZnFe, KRS-5, ya$a ya$a ya$a, and finally stumbled across a fact that good old optical glass plays nicely with the little bandwidth that I am going to study.

The latest problem that raised an objection was that the OPT101 sensor has a response band on both the visible and near infrared. Ouch. I was going to get a lot of false readings, and didn’t want to fool myself into thinking that the harvested data was a success. How to block visible light, and keep near infrared out on a budget, like mine ? After a quick Google search, Dichroic scrap bubbled to the surface. So did a UK infrared camera in Hawaii. They both started to look like resources that I could tap into.

I started to see how much of such and such I needed, and sent off an email to the UK handlers of the infrared camera and see if they could part with 9mm x 7mm of filter. I sent the email too soon, as I quickly realized that I could manufacture my own. Not of dichroic glass, mind you, or of what must have been a very expensive bandpass filter that they employ. A simple imposition of polarizing film would be what I would experiment with, first. If it doesn’t work as planned, I’ll call out the Cavalry! Two sheets at 90 degree angles should, in theory, block all visible light, and allow infrared light to pass thru. I sent a second email to the UK folks, and said, “never mind”. And sent up my order, thru eBay, once again; this time for display screen polarizing film.

I think I have everything moving in the right direction. I have cleaned up my attic, and set aside a good deal of space to relearn micro-controllers, and programming. I have spent many hours with telescope time, learning how not to get lost in the night sky. Have ordered gold leaf, polarizing film, and a couple of OPT101’s (one to destroy – always happens, one to prototype with, and one to make permanent), and will repurpose my old telescope.

To insure a future initiative, I have enrolled in a free Microsoft Visual Basic suite, to relearn programming (this time with a Windows 10 application in mind) – with the intent of the follow on project controlling a one-axis right ascension controller, with a Windows 10 phone, via text messages from my Mac, from a remote location. The same phone, will be suspended with a clear view of the site scope optics and provide a visual feed, as well as the near infrared live data and sky temperature. My current drive controller is old school and is crystal based. It isn’t properly tuned for my mount and is mostly useless. So I ditch the store bought controller, and marry up the single axis drive, as is, with an Arduino properly programmed for precise control. Sounds promising. And should add a few months of what is a personally rewarding hobby.

I am planning on having the near infrared telescope prototype ready for February, 2017. Reality may bite, and that may change to February 2018 !! However, the plan, all the same, is to position the scope, in a “fixed” position to observe a slice of the night sky, as it passes overhead. And as the world turns, so goes the right ascension, as near infrared light energy will converge to be recorded, on my laptop, one locus, at time. I am also going to repurpose the poor man’s lidar to monitor sky temperature. As a minimum, if a bird were to fly overhead, I would have rather high “sky temperature” to invalidate any near IR readings from the telescope.

February may not give me excellent results, and life may throw a few hurdles my way. And I am, or will be patiently waiting for next November 2017 for better skies, or the following year. It does not matter if the prototype works, or not. It may very well lead to an amateur discovery that wasn’t even expected, or planned for. What is of particular importance to me, is that I get to share something of myself, with all of you, right now. Thank you, all, once again, for the opportunity to write to you, on Sidereal Times, the official publication of the Amateur Astronomers Association of Princeton. And special thanks to both our President, Rex Parker, who threw out the challenge to all of us, to write for our publication, and to our editors that will try to make sense out of my Steinbeck school of writing.

Part II

Sunday, November 27th.

I finally got a chance to coat the Jason Model No. 327 Equatorial Reflector Telescope mirror in gold. It wasn’t too difficult – however the results are far from professional.

If I run into zero chances of success, later in the game – I will start from scratch and re-coat. It’s only a few dollars waste, so no worries on budget. For now, like any other endeavor, let’s move on with momentum, and steer clear of inertia. And work with what I’ve got, so far…

It turns out that that there were three screws that secure the entire mirror assembly. After their removal, the entire assembly came out, without much of a fuss. And yes, I did confuse at least one screw, upon reassembly – so I may have moved the mirror out of collimation, somewhat. I backed off my mistake – and checked visually. It seems OK. You old astronomer experts must be chuckling, by now – remembering your first miss-steps. You might agree that I am having all the fun, right now!

Coating the mirror with a penny’s worth of gold wasn’t very fun, though. However I managed to get most of the mirror coated. If I had to guess, I’d say 95% or more success in a very short time. As an aside, please note that I whetted the mirror with lens cleaner (I think that the solution is mostly isopropyl alcohol). The fluid assisted in adhering the gold leaf to the mirrored surface. A lightly sprayed surface, is all it took to assist this application.

After reassembling the mirror back into the telescope – I did a quick “eye” peek thru the rack and pinion focusing tube (without any eyepiece) and saw quite the mess. Not a pretty sight! All that wrinkly, square pieces of gold foil, overlapping each other. Not for the feint of heart. What kept me sane, was remembering that this was cheaper than a real commercial coating. So far…

I installed an SR 4MM, and pointed the business end of the 4.5 inch Jason towards the sky (not sunward !!) and was amazed to see that most of the light appeared white – to an “off-white with a bluish hue”. And despite moving the rack and pinion knob thru the full range of focus -and out of focus- the poorly applied gold leaf; with all its tears and aberrations, simply did not show up at 4MM. Truly, I wasn’t certain what I would see, other than say, “gold” color.

Perhaps there is a good amount of visible light transmission thru the gold leaf, and back from the mirror. Not too much of a concern, as I will be installing polarizing film later in the prototype.

Either the smaller areas that were left uncoated are reflecting a ton of light (not likely) or the gold leaf is reflecting light (probable). I must also contribute, that the light that I see – may be incidental and not coming from the mirror at all. Sigh. Light bouncing off the insides of the OTA.

Judging from what I see in the sky, this early afternoon – cumulus clouds abound – is a pretty good sign for a mostly clear sky, tonight. AAAP Clear Sky Chart shows minimal cloud cover, and above average seeing, too, for tonight (November 27, 2016). So, perhaps I do not have to wait too long to see the “visual” results (sans the sensor)!

The idea behind the gold leaf was to improve any infrared reflectance – so that test will have to wait until I can hook up the Near IR sensors, next weekend. I’ve been hunting the web for ideas on installing the sensor and it appears that as long as I follow the manufacturers data sheet – I should get some valid results.

I expect a tight range of voltages and to convert and expand them into a number range that I can plot in Excel. As for the remainder of today’s prototype setup – to see any star light tonight – will be a fun “seeing” thru a thin gold coating.

Posted in December 2016, Sidereal Times | Tagged , | Leave a comment